First Wedding Cake Emergencys

I am make ing a very plain 3 square wedding cake for june 13. I need a very sturdy white vanilla wedding cake reciepe. Also a really good crusting butter cream. I am scared to death. I have made baby shower and birthday cakes and have been told for absoultley no training I do very well, Guess i just need a few points from you experts PLEASE!! if you want to email me is [email protected]